calculate_corrosion() R function from [tidywater]

Calculate six corrosion and scaling indices (AI, RI, LSI, LI, CSMR, CCPP)

calculate_corrosion takes an object of class "water" created by define_water and calculates corrosion and scaling indices.

Source

AWWA (1977)

Crittenden et al. (2012)

Langelier (1936)

Larson and Skold (1958)

Merrill and Sanks (1977a)

Merrill and Sanks (1977b)

Merrill and Sanks (1978)

Nguyen et al. (2011)

Plummer and Busenberg (1982)

Ryznar (1946)

Schock (1984)

Trussell (1998)

U.S. EPA (1980)

See reference list at https://github.com/BrownandCaldwell-Public/tidywater/wiki/References


calculate_corrosion(
  water,
  index = c("aggressive", "ryznar", "langelier", "ccpp", "larsonskold", "csmr"),
  form = "calcite"
)

Arguments

water: Source water of class "water" created by define_water
index: The indices to be calculated. Default calculates all six indices: "aggressive", "ryznar", "langelier", "ccpp", "larsonskold", "csmr" CCPP may not be able to be calculated sometimes, so it may be advantageous to leave this out of the function to avoid errors
form: Form of calcium carbonate mineral to use for modelling solubility: "calcite" (default), "aragonite", or "vaterite"

Returns

A water class object with updated corrosion and scaling index slots.

Details

Aggressiveness Index (AI), unitless - the corrosive tendency of water and its effect on asbestos cement pipe.

Ryznar Index (RI), unitless - a measure of scaling potential.

Langelier Saturation Index (LSI), unitless - describes the potential for calcium carbonate scale formation. Equations use empirical calcium carbonate solubilities from Plummer and Busenberg (1982) and Crittenden et al. (2012) rather than calculated from the concentrations of calcium and carbonate in the water.

Larson-skold Index (LI), unitless - describes the corrosivity towards mild steel.

Chloride-to-sulfate mass ratio (CSMR), mg Cl/mg SO4 - indicator of galvanic corrosion for lead solder pipe joints.

Calcium carbonate precipitation potential (CCPP), mg/L as CaCO3 - a prediction of the mass of calcium carbonate that will precipitate at equilibrium. A positive CCPP value indicates the amount of CaCO3 (mg/L as CaCO3) that will precipitate. A negative CCPP indicates how much CaCO3 can be dissolved in the water.

Examples


water <- define_water(
  ph = 8, temp = 25, alk = 200, tot_hard = 200,
  tds = 576, cl = 150, so4 = 200
) %>%
  calculate_corrosion()

water <- define_water(ph = 8, temp = 25, alk = 100, tot_hard = 50, tds = 200) %>%
  calculate_corrosion(index = c("aggressive", "ccpp"))

calculate_corrosion function